Joint for metal tubes



f .sAvjoN. JOINT FOR METAL TUBES.v APPLICATION FILED MAR. `24. |919.

' Patented Feb. 3,1920.

Fig. v1

'of withstanding UNITED sTATEs PATENT oEEIoE.

ROGER S'AVON, 0F PARIS, FRANCE.

JOINT Fon. METAL TUBE-s.

Total? whom t may concern:

`Be it known that I, ROGER SAvoN, a 'citi-l parts, is a matter of rathergreat diiiculty.'

.At present such assemblage is eflected'either by brazing or weldingwhich have the serious drawback of' reheating the metal and thus causingit to -lose a portion of its strength, or by soldering, which produces ajoint that is much weaker than the tube itself.

The present invention has for its object to provide an improved jointfor metal tubes that is unattended by these drawbacks. This improvedapparatus comprises essentially an internal member for the tube, formedexternally with grooves, upon which the tube is fixed with a driving fitby a suitable process (beading, circular rolling, constrictlng) in sucha` manner as to enter the said grooves, and an outer hoop formed withinner corrugations corresponding in shape to the shape of. the groovesof the internal member. This hoop is forced on to the tube. Thisassemblage is capable of withstanding effectually the pulling forces inthe direction of the length ofthe tube. Longitudinal recesses may beformed in the vk'outer sur! face of the inner member, and the tube maybe forced upon the said lnner member 1n such a manner as to enter thesald recesses when it is desired that the assemblage shall 1 be capablealso of withstanding twisting` strains. In this manner very rotaryshafts can be produced.

The preferred method of construction is described byway of examplehereinafter and illustrated in the accompanying drawings, in itsapplication to the assemblageof a tube upon a circularly flanged or`swelled art. 1. p Figure l is an' external View thereof with a portionbroken away. Fig. 2 is a cross section on a line A-.B of Fig. 1.

light tubular Specification of Letters Patent.

Patented Feb. 3, 19.20.

Application led March 1919; Serial No. 284,866.

The swelled part l is formed on the outer surface with a certain numberof annular grooves 2, and also with a series of longitudinal recesses 3.It ends ina part 4 of cylindrical shape externally, having a roundededge 5. The tube 6 is engagedV upon the y swelled part l, and is forcedinto the grooves 2 and the recesses 3` in such a manner as to entertherein. b A hoop 7 provided internally, with corrugations 8corresponding in shape to the shape of lthe grooves in the swelled part1, is forcibly driven on to the tube 6 in such a manner as to be held inthe grooves2. l

The fixing of the tube and of the hoop may be effected by any suitableknown process (beading, circular rolling, constrict- 1ng) hot or cold.The fixing of these two` parts may be done separately 4or in one singleoperation. The forcing of the tube into the grooves 2 opposes pullingstrains in the direction ofvthe'length of the tube.

The fixing of the tube in the recesses 3 opposes twisting strains.

This fixing may be done by means of a hooping press. Instead of beingannular, as shown, the grooves may be helical in form. In such a casethe hoop 7 forms, so to speakr'a nut, for which the swelled part 1 formsthe screw, having between them the thickness of the tube 6. The forcingof the tube may then be effected directly by screwing up the hoop. Thecylindrical end 4 ending in a rounded edge 5 is designed to do away withshearing strains on the tube that might occur with a swelled part havinga straight edge whenthe diameter of the tube 6 should tend to becomereducedv owing'to the action of the pulling strain.

This joint may serve either for assembling a. tube upon a swelled part,as in the example end to end. In the latter case the inner memberconsists of a tubular member formed with external` grooves at its twoends and engaging halfA in each of the two tubes to be assembledtogether'. They external member is a hoop provided with innercorrugations corresponding to the said grooves. The two tubes are fixedupon the inner mem- -ber and then the hoop is fixed upon the twoadjacent ends of the tubes. The hoop may be a split collar with alclamping screw thread, and it may carry or be formed with axle pins orsockets for receiving other tubes in such a manner as to constitute ajunction shown, or for assembling two tubes placed piece for assemblingtubes extending in difinner member vformed with transverse eX- erentdirections. ternal grooves, and external longitudinal re- What I claimis:- cesses, a tube forced into saidgrooves and 1. In a pipe joint, thecombination of an said recesses, and an outer ring or hoop 15 5 innermember formed with transverse eX- formed with inner corrugationscorrespondterna'l grooves, a tube forced upon said inner ing in shape tothe shape of the grooves in member and an outer hoop formed With saldinternal member, forced in its turn inner corrugations corresponding inshape upon said tube. to the sha e of the grooves in thelsaid inner Intestimony whereof I have signed my 20 10 member, orced uponthe tube.name to this specification.

2. In a. pipe 'omt, the combination-of an ROGER SAVON.

